The modern golf course is maintained traditionally by irrigating, fertilizing, and mowing. The fertilization is commonly done by applying dry granular fertilizer and watering it in. During the year fertilizers of different ratios are applied as to the specific needs of the plant. Through the years liquid fertilizer has been applied to the course through the irrigation system by injecting it into the main line. This is a great labor saving practice for grounds keepers. This process uses a blended liquid fertilizer comprised of nitrogen, phosphorus, potassium, and micro-nutrients. These main nutrient elements are mixed into a recommended ration and applied to the course.
The quality blending of the liquid nutrients by the supplier is important to provide the needed nutrient ratios and to maintain storage life of the liquid. Some ratios are difficult to produce in liquid form and produce certain storage problems. Also the same nutrient ratio is injected on the entire course. In some cases different nutrients need to be added or eliminated to certain areas like the greens, tees, or fairways. Additionally, the user cannot change the fertilizer ratio until he has used the supply of nutrient in the storage tank and replaces it. These limitations prompted the design of this invention. The invention uses concentrated nitrogen, phosphorus, potassium, and micro-nutrients stored in individual tanks. This purity maximizes the storage life of the products. Each nutrient has its own injection pump and injection circuit to keep each nutrient separate until they are injected into the flowing main irrigation line. The desired nutrient ratio is obtained by setting the output rate of each injection pump. This is allowing an unlimited number of nutrient combinations with just four primary nutrients. These nutrient ratios can be changed as often as agronomic needs change for the plant. It also can be altered during the irrigation cycle to eliminate or add a specific nutrient to an area such as the greens, tees, or fairways.
The known prior art devices include those disclosed in U.S. Pat. Nos. 3,202,164, 3,421,738, 4,456,176 and 4,786,712. All these patents apply a premixed, blended single nutrient. They do not have the ability to alter the nutrient blend ratio of the stored nutrient.
This invention, which controls the independent injection of the four nutrients, will further reduce the use of chemical fertilizers by integrating plant tissue analyzing with the fertilizer program. This analyzing will evaluate the actual plant tissue nutrient needs based on each nutrient. With that determined the injection system can be adjusted to the exact nutrient ratio the plant requires and application will only apply what the plant will take up. This reduction of chemical fertilizers, and the minimizing of runoff, and leaching, will greatly improve the environment.